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431.
A sulfanilamide resistant strain Ts-5 of Pseudomonas mallei was isolated in the experiments on sulfazine therapy of malleus. The spectrum and level of the strain cross resistance to sulfanilamides and trimethoprim were studied. The frequency of the SurTrr mutants of P. mallei was determined. Efficient antibacterial drugs for the therapy of malleus caused by the sulfanilamide resistant strain are recommended. 相似文献
432.
Investigated the effects of self-regulation as a moderator of the relations between coping efforts and psychological symptoms of children of divorce. The interactions of two dimensions of self-regulation (task orientation and approach-flexibility) and two dimensions of coping (active and avoidant) predicting children's postdivorce symptoms were tested using a sample of 199 divorced mothers and their children, ages 8 to 12. The approach-flexibility dimension moderated the relations of both active and avoidant coping with children's self-report of anxiety. At higher levels of approach-flexibility, active coping was negatively related to anxiety, while at lower levels of approach-flexibility, active coping was unrelated to anxiety. Avoidant coping was unrelated to anxiety at higher levels of approach-flexibility, whereas at lower levels of approach-flexibility, avoidant coping was positively related to anxiety. The task orientation dimension did not interact with coping, but had direct, independent effects on children's self-report of conduct problems, depression, and parent-report of internalizing and externalizing behavior problems. The implications for understanding children's coping with divorce and future directions for research are discussed. 相似文献
433.
Identification of a common low density lipoprotein receptor mutation (C163Y) in the west of Scotland
WK Lee L Haddad MJ Macleod AM Dorrance DJ Wilson D Gaffney MH Dominiczak CJ Packard IN Day SE Humphries AF Dominiczak 《Canadian Metallurgical Quarterly》1998,35(7):573-578
BACKGROUND: The pathological processes by which Helicobacter pylori infection leads to the development of gastroduodenal disease are still incompletely understood. Oxygen-derived free radicals are important mediators of inflammation and potential carcinogens. Furthermore, dietary studies have suggested that antioxidant vitamins may protect against gastric cancer. OBJECTIVE: To determine plasma free radical activity and antioxidant vitamin levels in dyspeptic patients and to correlate the results with H. pylori infection and tobacco smoking. SUBJECTS: Forty-three patients undergoing routine endoscopy for investigation of dyspepsia. METHODS: Plasma free radical activity was determined by measurement of thiobarbituric acid-reactive substances (TBARS). Plasma samples were also assayed for the antioxidant vitamins A, C and E. Gastroduodenal biopsies were obtained from all patients for histological examination. RESULTS: Plasma TBARS levels were significantly higher in H. pylori positive versus negative subjects (P < 0.03), smokers versus non-smokers (P < 0.04) and males versus females (P < 0.01). Multiple regression analysis revealed that after correcting for male sex and smoking there was no significant association between plasma free radical activity and H. pylori infection. Smokers had significantly lower levels of plasma vitamin C than non-smokers (P< 0.05); no differences were seen in vitamin A and E levels. Gender and H. pylori infection did not significantly affect plasma antioxidant vitamin levels. Gastroduodenal disease was present in all of the smokers compared with 67% of the non-smokers (P < 0.05); 69% of the smokers were H. pylori positive versus 53% of the non-smokers. CONCLUSIONS: Tobacco smoking and male sex, both recognized risk factors for gastroduodenal disease, appear to be the major determinants of increased plasma free radical activity in dyspeptic subjects, rather than H. pylori infection. The reason for the higher prevalence of H. pylori infection and gastroduodenal disease in dyspeptic smokers is unclear but may relate to weakened antioxidant defences. 相似文献
434.
The results of computed tomography (CT) was compared with ultrasonographic and angiographic findings in 168 patients. All data of radiation diagnosis of abdominal aortic aneurysms (AAA) were compared with those of operations and morphological studies of the resected fragments of the aortic parts changed due to aneurysms. These comparisons provided a detailed characterization of the potentialities of CT performed on a third-generation unit in the presurgical diagnosis of this abnormality. At the same time, detailed XCT findings (semeiotics of AAA and their complications, such infiltration, dissection, and rupture) are given. The study shows benefits of the refined AAA by applying routine CT. The paper gives a diagnostic algorithm of using radiation studies (ultrasonography, CT, angiography) in the diagnosis of AAA. Third-generation CT units widely used in clinical practice are shown to provide necessary and complete information on the magnitude of AAA. This makes it possible to extend the capacities of timely detection of this abnormality and to make a successful surgical intervention. 相似文献
435.
V. N. Karnaukhov M. G. Mozerov 《Journal of Communications Technology and Electronics》2016,61(12):1426-1431
In this study, an original method for restoration of multispectral images by means of gradient reconstruction is proposed. The method uses a simple relationship between the gradient at the neighboring points in the distorted image and the gradient at distant points in the initial image. The result of restoration by the proposed algorithm excels the result obtained by the standard method based on the Wiener filtering. A new method for estimation of the parameters of the distorting motion-blur operator is also proposed. In this case, the blurred image is considered as a superposition of M shifted original images, and the autocorrelation convolution of the distorted image can be represented as a linear combination of M 2 mutual convolutions of several identical shifted images. Thus, the autocorrelation function of the distorted image is a straight line passing through the center, and the direction of this line and its length coincides with the parameters of the distorting operator. As compared to the best present-day algorithms, the proposed method exhibits higher accuracy of parameter estimation. In addition, computation of parameters with the use of this method takes much less time than with the use of popular estimation algorithms based on the Radon transform. 相似文献
436.
O. E. Stepanov V. E. Karnaukhov A. M. Khudyakov Yu. N. Eikhorn A. V. Bulanov M. L. Lukashenko I. M. Dikarev O. V. Logashev 《Thermal Engineering》2014,61(3):203-209
Several relationships were analyzed to calculate the heat transfer during boiling water with underheating involving these implemented in RELAP5 and KORSAR codes. The errors of the presented relationships are evaluated using modeling of the experimental data on boiling with underheating in vertical channels. It is shown that the quantitative evaluations of the wall temperature during boiling with underheating, which are obtained applying the codes, can be refined by means of the involvement of the alternative trailing relationships, which is topical in connection with the influence of surface boiling on the intensity of the nodular (hot-spot) corrosion of the fuel element claddings. 相似文献
437.
ELÇIN DEMIRHAN DILEK KILIÇ APAR GIZEM PAYER BELMA ÖZBEK 《International Journal of Dairy Technology》2011,64(3):402-407
In this study, the effect of initial kefir grain concentration and various minerals (MgO, MgSO4.7H2O, ZnSO4.7H2O, CaSO4.1/2H2O and Fe2O3) on the propagation of kefir grains and the pH evolution of kefir were investigated. The activated kefir grains were inoculated into very low fat (0.1%) cows’ milk under constant temperature (25°C) and impeller speed (100 rpm) for a propagation time of 24 h. Several mathematical models proposed to predict the pH value and kefir grain biomass increase vs propagation time were evaluated by the experimental results for all mineral additions; the Richards equation was found to be the most appropriate one. After evaluation of the experimental data, the most influential mineral addition providing 46.3% increase in kefir grain biomass was found to be MgO with a concentration of 0.30 g Mg2+/L. At this optimal condition, a model was derived for the kefir grain biomass concentration representing pH dependence. 相似文献
438.
439.
To investigate the role of Srp54p in protein translocation, the Yarrowia lipolytica SRP54 homolog was cloned. Sequencing revealed an open reading frame of 536 amino acids coding for a 57·2 kilodalton polypeptide with 55 to 57% sequence identity to Srp54ps of Saccharomyces cerevisiae, Schizosaccharomyces pombe, and mouse. Like these Srp54ps, Y. lipolytica Srp54p has an N-terminal domain with a highly conserved GTP-binding site and a methionine-rich C-terminal domain. Differing results regarding the essentiality of SRP subunits were obtained. SRP54 is important but not essential for growth, but it was reconfirmed that at least one SRP RNA gene is essential. Cells with SRP54 deleted grow about six times more slowly than wild type; faster-growing colonies, still growing much slower than wild type, appeared quite frequently. In srp54Δ cells, no untranslocated alkaline extracellular protease precursor was detected. Therefore, to develop another reporter molecule the Y. lipolytica KAR2 homolog was cloned and Kar2p antibodies were produced. For Kar2p an untranslocated precursor was detected in srp54Δ but not in wild-type cells, suggesting that its translocation was defective in the srp54Δ cells. These results confirm an in vivo role for SRP in protein translocation in Y. lipolytica, suggest that SRP RNA or an SRP core-particle has functions not shared by Srp54p, and show that, as in S. cerevisiae and Sz. pombe, reporter molecules differ in their dependency on SRP for translocation. The SRP54 and KAR2 sequences have been deposited in GenBank under Accession Numbers U42418 and U63136. 相似文献
440.